<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>原生Ajax</title>
  </head>
  <body>
    <input type="button" value="获取数据" onclick="getData()" />

    <div id="div1">
      
    </div>
  </body>
  <script>
    function getData() {
      //1. 创建XMLHttpRequest
      var xmlHttpRequest = new XMLHttpRequest();

      //2. 发送异步请求
      xmlHttpRequest.open("GET","http://yapi.eehp.cn/mock/61/user/findAll");
      xmlHttpRequest.send(); //发送请求

      //3. 获取服务响应数据
      xmlHttpRequest.onreadystatechange = function () {
        if (xmlHttpRequest.readyState == 4 && xmlHttpRequest.status == 200) {
          document.getElementById("div1").innerHTML = xmlHttpRequest.responseText;
        }
      };
    }
  </script>
</html>
